The objective of this research work is to compare the environmental impact, expressed in terms of non-renewable cumulative energy demand (CEDnr) and greenhouse gas (GHG) emissions, of nine architectural visions for a new neighbourhood located in the periurban area of Lausanne in Switzerland. The visions have different morphologies and their buildings are furthermore declined in a series of constructive scenarios generated by varying parameters such as the type of insulating material or the heating system. In order to compare and analyse the results of this multi-variant evaluation, the target values established by the SIA 2040 and resulting from the 2’000-Watt society concept are used as a reference framework. The present study offers a double perspective allowing both a comparison of the environmental impact of the different visions between them, but also an exploration of the results of a parametric analysis carried out for each of them. This double approach allows to highlight on the one hand the influence of the urban morphology proposed by each vision, and on the other hand the room for manoeuvre at the level of materialisation that each vision presents intrinsically.